The present invention relates to an electropneumatic positioner for converting an input electrical signal into an air pressure by using an electropneumatic converter, and supplying the air pressure to an operating unit, thereby controlling the valve opening degree of a regulating valve for opening/closing a channel.
When an electropneumatic positioner including both a positioner function and an electropneumatic conversion function and serving as a kind of air pressure servo mechanism is to be newly installed or replace an old one, various settings, zero/span adjustment, and tuning of control parameters must be performed on the site of installation. Note that zero/span adjustment and tuning of control parameters are also performed in regular maintenance.
According to a conventional electropneumatic positioner, however, an operator performs the above various settings, zero/span adjustment, and tuning of control parameters. This imposes a heavy load on the operator, resulting in many mistakes. This tendency becomes noticeable when various types of adjusting valves are combined with each other.